Geographically distributed entities, such as a business with multiple local offices in different geographic locations, frequently desire to maintain a logically unified proprietary network that is accessible by all of the geographically distributed entities. To accomplish this, a wide area network (WAN) may be used to link the different locations.
Information technology (IT) managers within geographically distributed entities face the conflicting requirements of keeping costs in check while providing users with new and faster applications. This conflict is most acute on the WAN, where costs can be high and obtaining applications to perform well is hampered by limited bandwidth and high latency.